Periampullary gangliocytic paraganglioma: a case report.

A case of gangliocytic paraganglioma of the ampulla of Vater is reported. A 62-year-old female patient with abdominal discomfort and intermittent upper gastrointestinal bleeding was admitted for further diagnosis. Endoscopy revealed a broad-based periampullary polypoid mass. A mesenchymal neuroectodermal lesion of uncertain malignant potential of the intestinal submucosa was reported on frozen sections performed during exploratory laparotomy. Subsequently, a benign gangliocytic paraganglioma was diagnosed on paraffin-embedded tumour tissue. Gangliocytic paragangliomas are tumours of uncertain histogenesis. Entrapped intratumoural muscle fibres and artificially loosened accumulations of ganglion cells may potentially mimic malignancy, predominantly on frozen sections. It is important to recognise this rare, benign mesenchymal tumour in order to avoid possible surgical over-therapy.